An
American idiom (now apparently co-opted by other English-speaking countries) that means to
restart a project, or
reformulate an idea. Presumably comes from professions that utilise a
drawing board or
drafting table to formulate designs, such as engineering and
architecture. The earliest occurrence of the phrase appears in a 1941
New Yorker cartoon by
Peter Amo. The cartoon depicts a fiery airplane crash with two men speaking, the caption reading: "Well, back to the drawing board."
Example:
The budget for our project was slashed so we have to go back to the drawing board. (Our idea now requires more money than we have, so we have to think of a new way to do the project.)